Milk Thistle Extract for HorsesMilk thistle extract (Silybum marianum), also known as St. Mary’s thistle, is an herbal supplement primarily used to support liver function in horses.

Milk thistle seeds and leaves contain many bioactive compounds, collectively referred to as silymarin. Silymarin is a flavonolignans with antioxidant, anti-inflammatory and immunomodulating properties.

It can be used to provide nutritional support to horses dealing with inflammation including inflammatory airway disease or allergies and may help with neuropathic pain in chronic laminitis. [12] The antioxidant properties of milk thistle can help horses stay healthy and recover faster from exercise and illness.

The liver is a crucial organ involved in detoxification and metabolism of carbohydrates, fats, and proteins. It breaks down toxins in the body for elimination and is therefore susceptible to injury or damage.

Older horses are likely to benefit from nutritional support of liver function because they have a longer period of lifetime exposure to toxins that could affect liver health.

Horses with equine metabolic syndrome (EMS) might have excess fat deposits in the liver which can negatively affect its function, although this is rare except in advanced cases. These horses might benefit from milk thistle supplementation to support metabolic health.

Mad Barn’s Milk thistle extract seed extract is a dried, powdered form of the seed of the Silybum marianum plant. The recommended dose is 4.5 grams per day for a 500 kg horse. This can be provided as dried powdered added to the feed or as brewed tea poured over the feed.

Milk Thistle

5 stars
4 stars
3 stars
2 stars
1 star

Learn More

  • Supports liver function
  • Promotes hoof health
  • Antioxidant support
  • Used in metabolic horses

Benefits of Milk Thistle in Horses

Milk thistle is primarily known for its hepatoprotective effects, meaning it can protect liver tissue from damage and support the function of the liver. Because the liver affects so many physiological processes in the horse’s body, boosting the function of this organ can have wide-ranging benefits for your horse’s health.

Below are the top seven benefits of Milk Thistle extract:

1) Supports liver health

Milk thistle is well-documented to protect liver cells under many different conditions.

In rats given toxic doses of the drug paracetamol, Milk Thistle protected from fibrosis (scarring) and reduced liver enzyme elevations that were indicating liver damage. [13]

It was shown to significantly reduce liver enzymes and ultrasound findings of fatty liver in morbidly obese men and women. [14]

Silymarin, the Milk Thistle extract, has been shown to protect the liver via antioxidant, anti-inflammatory and antifibrotic effects in a variety of viral, metabolic and toxic liver diseases. [15]

2) Provides antioxidant benefits

The active ingredient silibinin found in this herb increases antioxidant protection in healthy horses. Horses given a high dose of silibinin for one week had higher levels of the antioxidant molecule glutathione in their blood.

Glutathione forms part of the antioxidant enzyme glutathione peroxidase, which combats reactive oxygen species (ROS) to prevent oxidative stress.

This improved antioxidant status helps maintain healthy cells and tissues, especially in the liver and intestine where silibinin will be most concentrated.

Increasing the availability of antioxidant enzymes in the liver helps to ensure the proper metabolism of nutrients like carbohydrates, proteins and fats, into energy without allowing oxidants (free radicals) to damage the cells. [2]

3) Modulates inflammatory responses

Laboratory studies have demonstrated milk thistle can prevent inflammatory responses in white blood cells exposed to lipopolysaccharide. [10]

This could help control systemic inflammatory responses in situations like retained placenta, colitis, intestinal damage and intestinal infections.

4) Counteracts high iron intake

Silymarin has iron chelating effects which could enhance detoxication processes to protect your horse from the damaging effects of excess heavy metal exposure. These chelating compounds bind iron and help reduce serum ferritin levels and iron stores in tissues. [11]

This might be especially beneficial to horses with iron overload. If you suspect your horse has high exposure to iron in their feed or water, you may want to consider supplementing their diet with milk thistle.

In humans that are genetically prone to iron overload, milk thistle seed was shown to decrease iron absorption. [3]

5) Provides anti-inflammatory benefits

Milk thistle extract has been shown to exhibit anti-inflammatory benefits in animals and humans, particularly when there is an immune challenge like an infection. It lowers pro-inflammatory cytokines which trigger immune responses.

In the short term, pro-inflammatory cytokines are beneficial because they help to clear out an infection, but if they are present at high levels for extended periods of time they can cause tissue damage. Milk thistle can help protect tissues by moderating the levels of pro-inflammatory cytokines. [4]

6) Can dampen allergen hypersensitivities

Horses that have recurrent allergies like